Not all sf made it into the Penguin Science Fiction series. The sf novels of Orwell, Huxley and L P Hartley all remained outside, presumably because most of their output was non-genre or 'mainstream' fiction and it is on these shelves that book buyers would look for the authors' works.

However, the same could not be said of John Christopher and John Wyndham. A reprint of Christopher's The Death of Grass had been due to launch the Penguin sf series back in March 1963 alongside Olaf Stapledon's Last and First Men. But the reprint was put back four months, and when it appeared it was simply packaged as 'a Penguin Book'. The banner was used again a month later for Wyndham's Trouble With Lichen and repeated for other books by these two authors.

The reason stemmed from Wyndham's reluctance to have his work labelled as sf, and his insistence that Penguin market his books as mainstream fiction. The two Johns were good friends, so is was perhaps inevitable that the reluctance of one should rub off on the other. The use of abstract or surrealist cover art was also avoided, though arguably to the detriment of the books themselves, whose pictorial covers paled alongside the modern art being used in the sf series.

Wyndham's desire to be seen as a mainstream author was never quite realised. To readers and critics alike he was an sf writer and always would be. For ultimately sf is whatever readers identify as sf, or, as Harry Harrison once put it, "sf is what I am pointing at when I say science fiction". This, and other tautologies like it, reveal the difficulty of trying to define sf, for while the debate continues the fact remains: science fiction is science fiction, as sure as eggs is eggs.

Utopian fiction was less common in the twentieth century than its dystopian counterpart and by no means all utopias, or indeed dystopias, are sf. The idea of a perfect society stretches back to Greek antiquity and Plato's Republic, though the term 'utopia' was first used in 1516 as the title of Sir Thomas More's novel about an imaginary island free from poverty, crime and other social ills. Neither The Republic nor Utopia is science fiction, of course; the time for that was during the second half of the nineteenth century when a wave of utopian sf appeared, peaking in 1888 with the publication of Edward Bellamy's Looking Backward (later published in the Penguin American Library). Aldous Huxley's Island is one of the more recent utopias that qualifies as sf, if only by way of contrast to the Brave New World he created 30 years earlier.

Consider Her Ways and Others was a Penguin with a peculiar cover by Herbert Spencer, the founder and editor of the influential design journal Typographica. Spencer's blurred image of a giant syringe puncturing a doll's arm at first suggests he had misread the cover brief and confused heroine for heroin, though in fact it is a trippy reference to the title story.

It is not uncommon for mainstream authors to try their hand at sf, so L P Hartley's presence here is no great surprise. Though best known for The Go Between, Hartley's one attempt at sf produced Facial Justice, a dystopian yarn set some time after a third world war, when only isolated pockets of humanity remain. The novel tells the story of Jael 97, a young woman living in a post-apocalyptic community whose unseen dictator turns out to be a little old lady, thus recalling in all but gender the eponymous ruler in L Frank Baum's classic childrens' story, The Wonderful Wizard of Oz. But unlike Oz this is a society where women who are considered either alpha (pretty) or gamma (ugly) are encouraged to undergo plastic surgery to make them beta, or pretty ugly. This is done to promote equality and banish envy, and while the gammas are keen, the alphas are less so, for this is no nip and tuck – the entire face is removed and replaced by a synthetic one.

The novel brings new meaning to the term 'losing face' and like Bernard Wolfe's sf novel Limbo '90 it is full of wordplay. With slogans such as "betafied means beautified" littering the narrative, Hartley's tongue-in-cheek (it is tempting to say facetious) intentions are all too clear. Perhaps he should have taken a leaf out of his own book, for if surgery is the solution then this is a novel in need of a scalpel. As a short story it might have worked better. Or should that be beta?

The artwork for the 1966 reprint of Huxley's Island is more in keeping with the novel's utopian ideals than its pyrotechnic cover of two years earlier. With no Marber grid or Penguin banner, the image fills the entire cover, suffusing it with an aura of zen-like calm. One could be forgiven for thinking that the man in the water is day-dreaming rather than ship- wrecked and half drowned as he floats face up in the shallows of the novel's eponymous isle.

At first glance the intricate web-like pattern on his face and head brings to mind the use of henna for body decoration, a custom practised in parts of Asia and a reference to the novel's geographical setting. But on closer inspection the pattern reveals an Arcadian shoreline, and like the island he is drifting towards, his face is a cliff face, replete with tropical vegetation. "No man is an island", wrote the English metaphysical poet, John Donne, in 1624. Well, this one is.